High Quality Content by WIKIPEDIA articles! CatDog is an American animated television series which premiered on April 4, 1998. The series was created for Nickelodeon by Peter Hannan. The cartoon "Fetch" was also shown in theaters with The Rugrats Movie. The series depicts the life of conjoined brothers, with one half being a cat and the other a dog. Nickelodeon at first ordered 40 episodes and planned to debut it in spring 1998. Nick produced the series from Burbank, California.